Nighthawk X4 - WiFi Cable Modem Router - Unable to connect to 5ghz

[RegularDude]

Up until today, all of my devices have been connected to my 2.4ghz radio - with no issues.  Since I recently added a few new devices, I decided to spread them across both my X4's radios.  SSD only differs by radio type, they share the same password.  Details for each are broadcast, and all my devices can see both of them.  When I attempt to connect to the 5ghz radio, my devices are unable to do so.  On my cell phone, I can see that it attempts to connect 3 (or 5) times, but it is unable to connect.  Only error message it displays is 'unable to authenticate'.  I don't get any detailed info from my other devices.  The password for the 5ghz gets saved by each device, but again, none are able to connect.  I've stopped the 5ghz radio and restarted, to no avail - result is the same.  I've had this unit since February of this year and I've experienced no issues with it - until now.  Has anyone else encountered this issue?  Any advice for resolving it?  Any input is much appreciated.

[plemans]

Here's what I'd try.

1. log into your devices and "forget" the network.

2. log into the router and change the password/reset it to what you think it is. It isn't hard for a space to be at the end of a password and not realize its there. 

3. then try to reconnect. 

[RegularDude]

Thanks for the suggestion, plemans.  Just gave it a try, but that wasn't the issue (I hoped it was) - same result.

[plemans]

If you're using any special characters in your password, remove them. They can occassionlly create issues.

Another thing to try is to disable the password entirely. If it works, it means the wifi is fine, its something to do with the password setup or password itself. 

[RegularDude]

Okay, not sure why I didn't try that before.  I turned off the security and it functioned fine.  Once I add the WPA2-PSK [AES] security (and the SAME password as was entered for the 2.4ghz radio), I'm unable to authenticate then.  I tried the same password (which had no special characters), variants with caps and no caps, even all numbers (since the field can take 8-63 characters or 64 hex digits).  Once I create a PW to secure it, I can't authenticate.

[plemans]

Is it only certain wireless devices? Aka, android, IOS, smart devices?

What all types of devices are affected? 

Another thing you can possibly try is setting the 5ghz speed down. Shouldn't impact it but its worth a shot. 

[RegularDude]

Hey, plemans - this is occurring with my Android devices, smart televisions, Roku's, etc.  Basically any wireless device that I wish to connect to the X4 on the 5ghz radio.  By default, the speed is set to 'Up to 2165 Mbps'.  Last night, I dropped it down to 'Up to 1000 Mbps', to match the speed setting of my 2.4ghz radio.  It didn't work when I tried it.  So I'm unsure where to go with this next.  The 5ghz works, but once I add a form of security to it, none of the devices are able to connect to it.  Those same security policies function perfectly on the 2.4ghz radio.  My devices are compatible with both bands - and it hasn't been an issue with my previous routers.

[plemans]

Have you tried a factory reset and reinstall? 

[RegularDude]

Not yet; I was purposely leaving that as the last ditch troubleshooting move.  I'll factory reset it after the weekend, have too many people on it right now.  As far as reinstall goes, what do you mean?  Reconnecting the other devices to the WiFi?

[plemans]

I just mean doing a manual re-install after the factory reset. Many use backup configurations which work well most of the time. But if a firmware changed enough between iterations, restoring a backup leaves the issues still there. 

[RegularDude]

Interesting.  So if I perform a factory reset, the firmware could potentially revert to an earlier version?  I guess I've been looking at this too much from the perspective of how cell phones handle version updates when a factory reset is performed (which preserves the most current version of the OS).  When I looked up this model on the Netgear Support site, so I could download and install the most current version of the firmware, it told me there was no firmware to download.  And that my internet service provider would update the firmware as necessary.  So I haven't had to install anything from day one.  I've made no backups of my configuration, as I've made few adjustments to the defaults. 

[plemans]

Factory resetting doesn't revert the firmware at all. What it does is remove all the prior settings. Sometimes firmware upgrades are big enough that a factory can help resolve issues caused from the changes.

You're correct in that you can't download firmware for it. Combo devices only get their firmware from the ISP. 

[RegularDude]

Got it, thank you plemans for confirming the results of a factory reset.  I'll give this a try come Monday.  The current behavior just doesn't make sense.  And I've scoured the UI; I didn't see anything that would restrict me to utilizing only one radio at a time.  So I'm hoping the reset will resolve the issue I'm experiencing.  And it's not a matter of distance from the router.  I can use any of my mobile devices from a seat right next to it and I just can't authenticate.  It goes through the motions of establishing a connection, but it just fails.

I'll let everyone know how this pans out.

[plemans]

If it doesn't work and you're still within your warranty, I'd start an RMA process with netgear.